JPS6342145Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Technical Field of the Invention The present invention relates to a die for sea-island composite fibers with excellent spinnability.

B. Prior art and its problems Conventionally, island-in-sea composite fibers, in which a single fiber contains multiple filaments that are substantially continuous in the fiber axis direction, have been effectively used as synthetic leather and synthetic leather-like textile materials. Various spinnerets have also been proposed for producing these sea-island composite fibers. The most common and excellent method for producing sea-island type composite fibers is to first substantially form a core-sheath type composite stream, then aggregate a large number of these fibers in a molten state, and then spin the fibers. .

This sea-island type composite fiber cap has a flow path for sea components between at least two upper and lower cap plates,
A cap is used in combination with a group of tubular bodies into which island components are introduced. However, in such a nozzle, the polymer of the sea component is introduced from the outer periphery toward the inner periphery (the center of the nozzle) of the ocean flow path formed by the two upper and lower nozzle plates. Since the nozzle plates are set parallel to each other, especially when using a large diameter nozzle, or when the ratio of sea components in the fibers is low and the discharge amount is low, the fibers are discharged from the outer periphery of the nozzle. There is a difference in residence time between the polymer discharged from the inner periphery of the nozzle, and the flow velocity of the polymer is lower in the inner periphery of the nozzle, and the residence time is longer, making abnormal retention more likely to occur. A difference in viscosity occurs between the inner and outer peripheries, and the polymer viscosity at the inner periphery decreases when spinning for a long time.

If spinning for a long period of time under such conditions, the viscosity difference between the sea component and the island component increases, especially in the inner periphery where the viscosity of the sea component decreases, resulting in defects where the island components adhere to each other and merge, resulting in the maintenance of a composite flow. In some places, holes are created where even the discharge of the sea component is no longer possible, and the number of spun yarn breakages increases.

Therefore, the life of the cap required to maintain the form of the sea-island composite fiber is extremely short, resulting in the drawback that the cap must be replaced quickly.

C. Purpose of the present invention The present invention was devised in view of the various shortcomings of the prior art, and its purpose is to eliminate the residence time difference and abnormal retention of the sea component remaining between the two spinnerets, and to prevent spinning. To provide a cap for sea-island type composite fibers which has excellent properties and can greatly extend the life of the cap.

D. Structure of the present invention That is, the present invention consists of at least two or more cap plates and a group of tubular bodies that serve as flow paths for island components, and
In an island-in-the-sea type composite fiber cap having a sea component flow path between two cap plates, the upper cap plate or the lower cap plate constituting the flow channel is tapered so that the space for the sea component flow path extends from the outer periphery of the cap. A sea-island type composite fiber cap is characterized in that it becomes narrower toward the inner periphery.

The present invention will be explained in detail below using drawings.
It goes without saying that the present invention is not limited to the following embodiments.

FIG. 1 is a sectional view of a conventionally commonly used die for sea-island composite fibers. In FIG. 1, the island component A is discharged from the discharge hole 6 through the introduction hole 5 provided in the No. 1 plate 1, and flows into the inside of the tubular body 7 implanted in the No. 2 plate 2. On the other hand, the sea component B is completely separated from the island component A by the packing of the packing grooves 14 and 14' provided in an annular shape.
An introduction hole 15 bored in a circumferential manner on the outer periphery of the number plate 2
After that, it is guided to an ocean current path 8 constructed between the second plate 2 and the third plate 3. Next, the tubular body 7 and the No. 3 plate 3
A single core-sheath type composite flow is formed in the flow path 10 by surrounding the island component A that is metered by the slit 9 formed between the two and flowing out from the inside of the tubular body 7. The composite flow is guided to a collection part 11 provided on the No. 4 plate 4, where a large number of core-sheath type composite flows guided from other channels formed in the same manner are collected and discharged from the discharge hole 12. A single sea-island composite fiber is formed. Here, 13 is an annular ring provided in the space between the second plate 2 and the third plate 3. As described above, by uniformly arranging the tubular bodies of the sea component introduction holes and the island component introduction holes on the base plate, a sea-island type composite fiber base is constructed. Since it is introduced in one direction from the outer periphery 16 toward the inner periphery (center) of the sea flow channel 8 formed between the plate and No. 3 plate, it is introduced concentrically in two or more rows. In a nozzle having a large number of sea-island composite flows arranged in an array, a difference in residence time between the sea-component polymer discharged from the outer periphery 16 of the nozzle and the sea-component polymer discharged from the inner circumference is likely to occur. The flow velocity of the polymer in the inner periphery is lower and dead spaces are more likely to form, resulting in heat-denatured polymer and a difference in viscosity between the inner and outer peripheries of the discharged polymer.
The viscosity of the polymer at the inner circumference decreases when spinning for a long time (for example, 10 days or more). If spinning for a long period of time under such conditions, the viscosity difference between the island component and the island component will increase, especially in the inner periphery where the sea viscosity decreases, causing defects in which the viscosity balance will be disrupted and the island components will adhere to each other and merge, resulting in a composite flow. can no longer be maintained, and in some areas, holes are created where even the discharge of sea components is no longer recognized, resulting in an increase in spun yarn breakage.

Therefore, the life of the spinnerets required to maintain the shape of the islands-in-the-sea type composite fiber is short, and the spinnerets must be replaced.

In order to solve this problem with the cap structure,
In order to reduce the space in the ocean current path formed by No. 2 plate 2 and No. 3 plate 3 from the outer circumference to the inner circumference, the No. 2 plate or No. 3 plate is tapered, and the inner and outer circumferences are tapered. This can be solved by reducing the difference in residence time between the two and eliminating abnormal retention areas.

FIG. 2 is a cross-sectional view of the sea-island type composite fiber die according to the present invention. In FIG. 2, members given the same reference numerals as in FIG. 1 indicate the same or equivalent members as those in FIG. 1.

In FIG. 2, the island component A is discharged from the discharge hole 6 through the introduction hole 5 provided in the No. 1 plate 1, and flows into the inside of the tubular body 7 implanted in the No. 2 plate 2. On the other hand, the sea component B is a packing groove 1 provided in an annular shape.
It is completely separated from the island component A by the packings 4 and 14', and passes through the introduction hole 15 which is circularly bored in the outer periphery of the No. 1 plate 1 and the No. 2 plate 2, and then the No. 2 plate 2 and the No. 3 plate. 3 and is guided to an ocean current path 8 formed between the seawater and the ocean. Next, the island component A that is metered by the slit 9 of the hole in the tubular body 7 and the No. 3 plate 3 and flows out from the inside of the tubular body 7 is surrounded, and one core-sheath composite flow is formed in the flow path 10. is formed. The composite flow is guided to a gathering part 11 provided on the No. 4 plate 4, and a large number of core-sheath type composite flows guided from other channels formed in the same manner are collected and discharged from the discharge hole 12. A single sea-island composite fiber is formed. 13 is an annular ring provided on the second plate 2 and the third plate 3. As described above, by arranging the tubular bodies of the sea component introduction hole and the island component introduction hole uniformly on the mouth surface, the sea-island type composite fiber mouthpiece is constructed as in the conventional method. Since the lower surface tapers downward from the outer periphery of the cap toward the inner periphery, the sea flow path formed between it and the No. 3 plate 3 gradually becomes smaller from the outer periphery toward the center. There is no abnormal retention in the tube, and there is no difference in residence time between the polymer discharged from the inner periphery of the nozzle and the polymer discharged from the outer periphery. Note that the angle of the taper of the second plate 2 is set to an optimum value depending on the number and arrangement method of the caps.

Further, in the above explanation, an example was explained in which the taper was provided on the No. 2 plate, but it is of course possible to provide the taper on the No. 3 plate.

E. Effects of the present invention In the present invention, a taper is provided in the upper or lower mouth plate that constitutes the sea component flow path.
The difference in residence time between the inner and outer periphery of the sea component that accumulates between the two cap plates is reduced, and abnormal retention can be eliminated, and the viscosity difference of the sea component, which was a conventional defect, is also eliminated, significantly extending the life of the cap. It can be extended to

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a conventional sea-island type composite fiber die, and FIG. 2 is a schematic cross-sectional view of a die according to the present invention. 1, 2, 3, 4... base plate, 5, 15... introduction hole, 6, 12... discharge hole, 7... tubular body, 8...
Sea channel, 9...slit, 10...channel, 11...
...Gathering part, 13... Annular ring, 14, 14'
... Packing groove, 16 ... Outer periphery.

Claims (1)

[Scope of utility model registration request] In a sea-island type composite fiber spinneret, which is composed of at least two or more die plates and a group of tubular bodies serving as a flow path for an island component, and has a flow path for a sea component between the two die plates, the flow path is configured. A sea-island type composite fiber cap characterized in that the upper cap plate or the lower cap plate is tapered so that the space of the sea component flow path becomes narrower from the outer periphery to the inner periphery of the cap.